This video says about itself:
15 October 2012
The first Caspian Stonechat for the Netherlands was discovered one week ago on Vlieland. It is a subspecies of the Siberian Stonechat, but is a candidate for reaching full species status. Whatever the status, it is a distinct and beautiful bird. The bird was in no rush to leave. We decided to give it a try and booked a ferry trip to Vlieland before continuing our birding weekend on Texel. Despite rainy conditions, we had perfect views of this nice bird. Especially the display of the raised and fully spread tail was a great sight.
There were then almost 280,000 birds on Vlieland.